down to the bone on the Matunuck

I am sanding on the bottom of my boat, up on the rocker; there was a big bubble in the fiberglass/epoxy.  I tried to sand it out enough to put epoxy in there and have wound up with a spot with fiberglass missing.  I then applied more epoxy.  But I am thinking I will have to sand it down completely and re-apply fiberglass.  Do some kind of patching on it, as if it were damaged by a rock. 

That sounds pretty drastic to me. 

This is on the bottom where two of the three panels of wood meet.  It is about eight inches from the stern.  I can see the wood, at it is right where the joint is. One of the panels is slightly higher than the other, hence the bubble formation.  There's no tack welding on that spot.  Of course the inside is glassed and filleted.  Is that strong enough?  Or will this be a weakness that I must fix now?  It is unsightly; I want to fix it, but how to best do it?

2 replies:

« Previous Post       List of Posts       Next Post »

RE: down to the bone on the Matunuck

I don't know the Mantunuck well enough to be qualified to say how necessary the glass is, but I can tell you that a glass patch is actually pretty easy and not that drastic at all.

First, get rid of the unevenness which caused the bubble in the first place.Either fill it in, sand it down or both. You're the builder on the spot so you have the best information to decide which is appropriate.

Next, just as you said, sand the area to get rid of the excess epoxy and to taper the edges of the remaining glass. You want to end up with a very shallow crater, 1 glass layer deep. I like to have my patches overlap for a couple of inches, so I make the radius of the crater be 2 inches plus the radius of the glassless area.

Once that's done, cut a piece of glass a couple of inches larger in all dimensions than the crater and wet it into place. If you wet out only enough of the patch to cover the crater, you won't get the dreaded glass snot from the unravelled threads. Once the patch cures to the green stage, you can get rid of the unneeded glass with a razor.

At this point, it's just a matter of feathering, filling and fairing which by now you must be pretty good at from building the rest of the boat.

Have fun,



RE: down to the bone on the Matunuck

Thank you, Laszlo.  I will patch it after all.  It sounds like an easy remedy, after all.  And it will give me practice for when I have to make repairs. 

« Previous Post     List of Posts     Next Post »

Please login or register to post a reply.